材料期刊网

分析了包层及衬底均为非线性Kerr型介质、芯区为线性均匀介质的三层平板波导的TE0模特性．理论分析及典型实例计算表明：对于自聚焦情况，模折射率增大时，芯区场的极大值逐渐减小，对于一定的光功率，模折射率与芯区折射率相等时，芯区的场分布呈均匀的“平台形”分布，而两侧场则迅速衰减；模折射率继续增大时，场分布的极值进入芯区两侧，而芯区场分布呈下凹形．给出了自聚焦对称三层平板波导TE0模的场分布曲线，功率随模折射率变化曲线及芯区功率与总功率之比随总功率的变化曲线．还计算了自散焦情况下的场分布及功率变化，在一定条件下，芯区也会出现等振幅分布．

The characteristics of TE0 modes in a waveguide with two identical Kerr type nonlinear claddings and a linear uniform core are analyzed. Both theoretical analysis and numerical examples give the same results. For the focusing case,with increasing modal refractive index, the maximum value of core field gradually decreases. At a definite optical power, when the modal refractive index at the core-cladding interface is equal to refractive index of core, the core field becomes uniformly 'platform-like', while the cladding field rapidly reduces. As the modal refractive index continually increases, the maximum field enters into the two claddings,while the field profile in the core changes to concave. Curves (focusing and defocusing cases) are given for field distributions, relations between modal index and power,ratio of core power to total power versus total power, relations between 'platform'height and core index, relations between 'platform' and core width, and so on.